Steels corresponding to S48C (JIS (Japanese Industrial Standards)) and S53C (JIS) or steels having improved cold forgeability described in Japanese Patent Publication No. 38847/1989 have hitherto been induction hardened and then used for outer races of constant velocity joints in automobiles. However, a reduction in weight of components is necessary in order to reduce the production cost and to improve the fuel consumption. To this end, the development of constant velocity joints having improved rolling fatigue life properties and torsional strength properties without sacrificing the cold workability of the above steels has been desired in the art.
Accordingly, it is an object of the present invention to provide a constant velocity joint for automobiles and the like, comprising a steel having improved rolling fatigue life properties and torsional strength properties without sacrificing cold workability, such as cold forgeability or machinability, of steels corresponding to S48C (JIS) and S53C (JIS) or steels having improved cold forgeability described in Japanese Patent Publication No. 38847/1989.